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    <script>
        function mergerSort(unorderArr, left, right) {
            if (left < right) {
                let mid = Math.ceil((left + right) / 2)
                mergerSort(unorderArr, left, mid - 1)
                mergerSort(unorderArr, mid, right)
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        mergerSort([3, 4, 6, 7], 0, 3)
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